Ceilidh ... Re^2: scf seems to converge, but I obtain wildly fluctuating mp2 gradients

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Re^2: scf seems to converge, but I obtain wildly fluctuating mp2 gradients

On Sat Jun 6 '09 9:05pm, Alex Granovsky wrote
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>2. At present, the only way to do this is to remove them manually from the basis set.
>Why not to use QMTTOL? Because it is not supported by Firefly.
>Why? The answer is here.
>In brief, this approach introduces errors to the almost
>all types of calculations requiring energy derivatives.
>We are working on alternative approach to automate or at least
>semi-automate deletion of basis functions, however, meanwhile
>you have to delete them manually (see the attached input and
>output files).

>Your system is an example of pathological case for SCF,
>so that I was forced to delete six S-type functions to achieve convergence.
>Perhaps I need to explain in more details how it was done.
>Please let me know if you need additional comments on this
>(iterative) procedure. Anyway, this would be the matter of
>a separate post.

Yes, a separate post on this iterative procedure would be highly appreciated, as there are several similar cases on hand.

>Finally, my guess is that using only 4 cores in parallel with default settings of $smp group should be faster.

comments on http://classic.chem.msu.su/cgi-bin/ceilidh.exe/gran/gamess/forum/?C3c360e4ddT5P-7152-909-00.htm http://classic.chem.msu.su/cgi-bin/ceilidh.exe/gran/gamess/forum/?C3c360e4ddT5P-7152-909-00.htm with attached file of completed output. The hessian part of the calculation could be faster using the 7/8 “brute force” approach?

>On Wed Jun 3 '09 1:51pm, Valentin Monev wrote
>---------------------------------------------
>>Dear Professor Granovsky,
>>Dear colleagues,

>>scf seems to converge, but I obtain wildly fluctuating mp2 gradients, on two core i7 machines running Windows Vista 64 and Windows 7 64 (each pc has cpu 920, two 1TB hard disks and 6 GB RAM). I cannot understand what causes these irreproducible results - see attached input and output files. Because the system calculated is somewhat large, I am using almost all (logical) processors in parallel using dynamic load balancing - seven out of eight possible (see attached batch file). Hyperthreading is enabled in the bios, but is effectively neutralized for firefly by $smp httfix=.f. httpar=.t. smppar=.t. $end. The cpu load is 89 % during scf and some parts of mp2, if I use -np 8 in the batch file, cpu load rises to 100% but I want to leave some cpu idle, to be able to use the pc for interactive work. The workload is balanced between the 8 logical processors, as shown by task manager - only one processor is somewhat less loaded. Dynamic load balancing seems much more effective than trying to use mklnp=2 in $system.
>>
>>
>>I tried to reproduce an mp2 calculation mp2grd.input.zip - see attached input and output files.

>>Any suggestions?

>>P.S. scf convergence seems flaky, but I couldn't find instructions on how to follow the suggestion in the output: YOU MAY CONSIDER DROPPING ONE OR MORE AOS, STARTING FROM THE END OF THIS LIST - any hints?

>>P.P.S. Is it sufficient to put pcgp2p.dll, fastdiag.dll, mpich_smp.dll and mpibind.dll in the folder containing the firefly.exe, and a path command that contains this folder? Should p4stuff.dll be in this folder?

>>P.P.P.S. Overclock: Turbo boost enabled; Gigabyte GA-EX58-UD4 mainboard bios setting CPU Intelligent Accelerator 2 set to Racing, i.e. 3.2Ghz (original 2.6) and 154 Mhz (original 133) under load; Performance enhance setting set to Standard (original Turbo); all voltages set to Normal (original Auto).

>>Help!
>>

Sat Aug 1 '09 5:38pm

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